Protein capture by G-quadruplex DNA for breast cancer profiling

Sweet, Taylor
Thumbnail Image
Other Contributors
McGown, Linda Baine
Wang, Xing
Lakshmi, K. V.
Issue Date
Terms of Use
This electronic version is a licensed copy owned by Rensselaer Polytechnic Institute, Troy, NY. Copyright of original work retained by author.
Full Citation
G-quadruplexes (G4s) are guanine-rich DNA sequences that fold both intermolecularly and intramolecularly to form four-stranded DNA structures. These structures come from self-stacking of two or more guanine quartets formed through hydrogen bonding. G4s can be further classified by their orientation such as parallel and antiparallel. Guanine quadruplex (G-quadruplex) structures are amongst the various structures found in aptamers. Aptamers have become an important alternative to antibodies as protein affinity reagents due to their comparable and sometimes even higher specificities than antibodies, their low to no immunogenicity, and their unlimited shelf life. However, aptamer discovery has had only limited success despite intensive efforts since their discovery in 1990. Recently, the McGown group introduced a new, human genome inspired "reverse" selection process to overcome some of these obstacles involved in aptamer discovery and enable greater representation of G4 structures due to the diversity found in the human genome. Instead of choosing an aptamer from a combinatorial library of random oligonucleotides for high affinity to a target protein as seen in the process SELEX, this approach uses G4-forming DNA sequences from the human genome to fish out specific-binding proteins from natural protein pools. We are particularly interested in G4-forming sequences in human oncogene promoter regions, where there is a tendency for G4 sequences to occur. The work described in this thesis focuses on protein capture from ductal carcinoma (breast cancer) tissue lysates of different stages by G4 sequences from the Rb, VEGF, and c-myc promoter regions. With these studies, we hope to eventually be able to profile cancers based on their stage and type.
August 2018
School of Science
Dept. of Chemistry and Chemical Biology
Rensselaer Polytechnic Institute, Troy, NY
Rensselaer Theses and Dissertations Online Collection
Restricted to current Rensselaer faculty, staff and students. Access inquiries may be directed to the Rensselaer Libraries.